1. Field of the Invention
The present invention relates to a polypropylene resin composition, and more particularly, to an olefin-based polypropylene resin composition which is suitable for use in forming interior and exterior materials of a vehicle, such as an interior trim and the like, and interior and exterior materials for vehicles formed from the same. The polypropylene resin composition has excellent physical properties such as high strength, impact resistance and the like, and is thus superior in resistance to damage, and further shows low gloss characteristics and excellent fluidity.
2. Description of the Related Art
In response to pollution caused by the automobile industry, interest has increased in the development of more environmentally friendly and energy efficient vehicles. For example, many automobile companies are developing a technology for a more lightweight vehicle body that will improve fuel efficiency.
Currently, the ratio of materials used for a typical automobile is about 65% metal and about 13% plastics. As metal materials applied to the vehicle body are increasingly replaced with plastic materials for reducing the weight of the vehicle body, the market share of plastic materials is increasing.
In particular, among the plastic materials polypropylene occupies a market share of about 35%. Polypropylene is inexpensive prices and has excellent processability. In particular, polypropylene can be processed through easy injection molding. As such, the market share and use of polypropylene as automobile interior and exterior materials, such as a door trim, a bumper, a side molding and the like, are increasing, particularly through the application of a highly flowable polypropylene having high fluidity characteristics and appropriate content control thereof.
However, when polypropylene having high fluidity characteristics is used in order to impart high fluidity characteristics to a polypropylene material, there is a problem in that the mechanical strength (flexural modulus) and impact resistance of the material are reduced.
Accordingly, an inorganic filler has been used in order to supplement the mechanical strength. However, there is a disadvantage in this approach in that the specific weight of the material is increased by addition of the filler. For example, when rubber is used in order to supplement impact resistance, and an inorganic filler is used in order to supplement the mechanical strength which is reduced by the rubber, the specific weight of the material is increased.
Meanwhile, due to high gloss caused by the inherent crystallinity of a polypropylene material, when polypropylene is used in an interior material, such as an automobile interior trim and the like, there is a problem in that the visual fatigue degree of a driver is increased and the aesthetics of the vehicle deteriorate due to the peculiar surface gloss imparted by the polypropylene.